KR20050044321A - Room temperature curable x-hnbr coating - Google Patents

Abstract

Elastomer coating composition are disclosed which cure at room temperature, and form highly flex-resistant, durable, and flexible protective layer on elastomers and provides excellent adhesion to elastomeric and metal substrates. The coating is a solvent solution of (A) a carboxylated hydrogenated acrylonitrile-butadiene copolymer, and (B) a room temperature isocyanate curing component. Coated bonded elastomer- metal composites are obtained without an additional application of heat to cure the coating.

Description

Room temperature curable X-HNBR coating

The present invention relates to protective coatings for elastomers.

Elastomeric materials are used in many industries. For example, elastomeric materials are used in the manufacture of installation, braking and insulation devices found in the engine compartments of various hoses, seals, automobiles and other vehicles. In addition, devices for installing engines in these vehicles typically consist of one or more metal parts adhesively bonded to one or more vulcanized elastomer parts. In these and many other industrial applications using vulcanized elastomeric materials, the elastomeric materials are typically exposed to various corrosive and degrading materials such as solvents, oils and fuels. Elastomeric materials tend to decompose upon exposure to these types of materials and research continues in the elastomer industry to produce elastomers that are resistant to corrosive materials.

One way to provide an elastomeric material that resists corrosive materials is to apply a protective coating to the elastomeric material. Various corrosion resistant coatings pre-used for flexible substrates (eg, elastomeric substrates) and rigid substrates (eg, steel, stainless steel, aluminum or plastics) include polyurethanes, polysulfides, and fluorocarbon elastomers. When applied to rigid substrates, it has been found that conventional corrosion resistant coatings such as fluorocarbon elastomers provide excellent resistance to oils and fuels. However, when applied to flexible elastomeric substrates such as natural rubber or polybutadiene, fluorocarbon elastomers suffer from poor fatigue resistance, poor low temperature properties, and poor adhesion to natural rubber or polybutadiene substrates.

US Pat. No. 4,472,88 describes hydrogenated copolymers of α, β-unsaturated nitriles and conjugated dienes containing active phenol-formaldehyde resin vulcanization systems. The U.S. patent describes a technique for bulk vulcanizates which is characterized by having excellent resistance to oxidative attack in hot air aging under oxidizing conditions and good compression set properties and good resistance to oil, but provides useful properties. There is no mention of suggesting that solvent based coatings may be formed on flexible elastomeric substrates such as natural rubber and polybutadiene.

U.S. Patent 5314955 describes a coating composition composed of (a) hydrogenated acrylonitrile-butadiene copolymer, (b) phenol resin, (c) curable component, and (d) solvent. This coating composition solves many of the problems of adhesion to rubber substrates combined with fatigue and fuel resistance. One of the disadvantages of the coating composition is that it requires a high temperature baking to cure the coating to promote adhesion to adjacent metal surfaces. Some parts, such as helicopter rotor bearings, are damaged by hot burning. Hot baking is also expensive to produce because it increases the time lag and additional processing of the parts. There is still a need for improved protective coatings on flexible elastomeric substrates such as natural rubber and polybutadiene, which are resistant to fatigue and temperature variability, exhibit effective adhesion to the substrate, and cure at room temperature.

The coating composition of the present invention is resistant to fatigue and temperature variability, provides good adhesion to flexible elastomeric substrates and cures at room temperature. In particular, the coating composition of the present invention comprises (a) a carboxylated hydrogenated acrylonitrile-butadiene copolymer (X-HNBR), (b) a curing component containing at least one isocyanate group and a group forming a crosslinking, and ( c) consists of a solvent. In another aspect, a coating of a substrate consisting of applying a solvent-based coating as described above to the surface of a vulcanized rubber substrate bound to a metal, drying the coating and applying heat in any case, at ambient conditions, to cause the dried coating to cure There is a way to do it. It is also desirable to provide a coating on the exposed portion of the metal around the perimeter of the elastomer. The present invention provides a coating for elastomer-metal composites having good adhesion to elastomeric substrates, good resistance to corrosive materials and good resistance to flexible fatigue over a wide temperature range.

(A) X-HNBR

In order to provide high saturation to the ethylenically unsaturated nitrile-conjugated diene rubber, the carboxylated nitrile butadiene rubber is hydrogenated. Hydrogenation serves to saturate at least 80% of the unsaturated bonds of the rubber. When the saturation degree is 80% or less, the rubber has low thermal resistance, and when the saturation degree exceeds the desired value of 99%, the elasticity of the rubber represented by the compression set or the like is excessively reduced. More preferred saturation of the rubber is 90-98%.

Conjugated dienes useful in preparing additionally hydrogenated carboxylated acrylonitrile-butadiene copolymers include 1,3-butadiene: 2-methyl-1,3-butadiene: 2,3-dimethyl-1,3-butadiene: 1, It may be a well known conjugated diene including 3-pentadiene: 1,3-hexadiene: 2,4-hexadiene: 1,3-heptadiene: piperylene: and isoprene, and currently 1,3-butadiene desirable.

Carboxyl groups have α, β-unsaturated monocarboxylic acids having 3-5 carbon atoms such as acrylic acid, methacrylic acid and crotonic acid and / or have 4-5 carbon atoms such as maleic acid, fumaric acid, citraconic acid and itaconic acid It is present in X-HNBR from other known carboxyl group-containing monomers such as α, β-dicarboxylic acid. Unsaturated carboxylic acid may be present in an amount from about 1% to about 10% by weight of the copolymer, which amount is substituted with the corresponding amount of conjugated diolefin.

Third optional monomer may also be used in the preparation of the polymer. The third monomer is preferably unsaturated mono- or di-carboxylic acid derivatives (such as esters, amides and the like).

Typically, the unsaturated nitrile comonomer copolymerized to form the carboxylated acrylonitrile-diene copolymer corresponds to the following formula.

Wherein A is hydrogen or a hydrocarbyl group having from 1 to about 10 carbon atoms. Examples of group A include alkyl and cycloalkyl such as methyl, ethyl, isopropyl, t-butyl, octyl, decyl, cyclopentyl, cyclohexyl and aryl such as phenyl, tolyl, xylyl, ethylphenyl, t-butylphenyl. Acrylonitrile and methacrylonitrile are presently preferred unsaturated nitriles.

X-HNBR copolymers are polymerized by the reaction of conjugated dienes, unsaturated nitriles and unsaturated carboxyl group-containing comonomers exemplified above in the presence of free radical initiators by methods well known to those skilled in the art. Suitable free radical initiators are beyond the ranges disclosed herein, and typically include hydrogen peroxide, benzoyl peroxide, cumene hydroperoxide, di-t-butyl peroxide, ascaridol, acyl peroxide, t-butyl hydroperoxide, Organic oxides such as trimethylamine oxide, dimethylaniline oxide, isopropylperoxy dicarbonate, diisobutylene ozonide, peracetic acid nitrate, chlorate, perchlorate, azobisisobutyronitrile, peroxides and hydroperoxides And azo compounds.

Commercially available preferred X-HNBRs are prepared from carboxylated nitrile-diene copolymers which are hydrogenated in two steps. It is known that c-c double bonds of 1,2-vinyl-aligned butadiene units in NBR are very rapidly hydrogenated and then the 1,4-cis sequence unit is hydrogenated. 1,4-trans ordered butadiene units hydrogenate relatively slowly. The NBR products used for hydrogenation are distinguished by the significant proportion of 1,4-trans sequence double bonds.

In two stage hydrogenation, the carbon-carbon double bonds are first reduced and then the carbon-nitrogen bonds are reduced. As is known in the art, this process avoids the gelation of the hydrogenated polymer that can occur if the reduction is carried out in one step. In the first step, different catalysts may be used, for example palladium or ruthenium catalysts. However, if desired, only nitrile groups may be reduced by suitable choice of catalyst, leaving unsaturated carbon-carbon bonds in the linear polymer chain. It is also possible to use a mixture of noble metals and nickel or cobalt by first operating at a relatively low temperature and then at a high temperature. Other techniques for hydrogenating acrylonitrile-butadiene copolymers are described, for example, in US Pat. Nos. 4,414,17, 47,153 and 4795788.

Typically, the most preferred acrylonitrile-butadiene copolymers are hydrogenated to the extent that the final product has an unsaturation level of about 1-20 mole percent, preferably about 3-7 mole percent.

Carboxylated hydrogenated nitrile rubbers (hereinafter referred to as "X-HNBR") are manufactured by Bayer under the trade name "Drban", for example under the trade name Durban KA8889. X-HNBR may preferably have an iodine value of about 50% or less, more preferably about 3-40%, most preferably about 8-30%. Resistance to heat and required solvents can be increased when X-HNBR with an iodine value of 50% or less (high hydrogenation rate) is used, and at low temperatures rubber elasticity can be used for the use of X-HNBR rubbers with low hydrogenation rate. Can be maintained. The median nitrile content of HNBR is preferably about 15-60%, more preferably about 30-55%, most preferably about 40-50%. The resistance to the solvent can be increased by the use of HNBR having a nitrile content of at least about 15%, in particular at least about 30%, and the low temperature resistance is of rubber having a nitrile content of less than about 60%, in particular less than about 50%. Can be maintained by. In addition, a Mooney Viscosity (hereinafter referred to as "Money Viscosity") as a median ML₁ ₊ ₄ (100 ° C) is preferably about 40-100, and a low Mooney viscosity of 40-60 is preferred for coating. . When X-HNBR having a Mooney viscosity falling within the above range is used, the coating composition exhibits high resistance to organic liquids and excellent flexibility and low temperature resistance.

(B) Curing Components

The curable component contains at least one isocyanate group and a group which forms a crosslink with X-HNBR. Preferred curing components contain at least one isocyanate group or group having isocyanate groups, and carboxyl reactive crosslinking groups. The curing component is best used at the level of 3-30 parts by weight relative to 100 parts by weight of the carboxylated hydrogenated copolymer of conjugated diene, unsaturated nitrile and carboxyl monomer.

Typical of curable components that can be cured at low temperatures are di- and polyisocyanates including aliphatic, cycloaliphatic and aromatic isocyanate functional compounds. Aromatic isocyanates are preferred. Specific examples of the di- or polyisocyanate include 1,6-hexamethylene diisocyanate: 1,8-octamethylene diisocyanate: 1,12-dodecamethylene diisocyanate: 2,2,4-trimethylhexamethylene diisocyanate: 3, 3′-diisocyanatodipropyl ether: 3-isocyanatomethyl-3,5,5′-trimethylcyclodecyl isocyanate: hexamethylene diisocyanate: 4,4′-methylenebis (cyclohexyl isocyanate): cyclophene Talene-1,3-diisocyanate: cyclodexylene-1,4-diisocyanate: methyl-2,6-diisocyanato caprate: bis- (2-isocyanatoethyl) -fumarate: 4- Methyl-1,3-diisocyanato cyclohexane: trans-vinylene diisocyanate and similar unsaturated polyisocyanates: 4, 4 'methylene-bis (cyclohexyl isocyanate) and related Lysocyanate: Methane diisocyanate: Bis- (2-isocyanatoethyl) carbonate and similar carbonate polyisocyanates: N, N ', N "-tris- (6-isocyanatohexamethylene) Aliphatic polyisocyanates such as biuret and related polyisocyanates. Aromatic di- and polyisocyanates include toluene diisocyanate: xylene diisocyanate: dianisidine diisocyanate: 4,4'-diphenylmethane diisocyanate: 1-ethoxy-2,4-diisocyanate benzene: 1-chloro-2 , 4-Diisocyanatobenzene: bis (4-isocyanatophenyl) methane: tris (4-isocyanatophenyl) methane: naphthalene diisocyanate: 4, 4 'biphenyl diisocyanate: m- and p Phenylene diisocyanate such as -phenylene diisocyanate: 3,3'-dimenyl-4,4'-biphenyl diisocyanate: p-isocyanato benzoyl isocyanate: tetrachloro-1,3-phenylene diisocyanate: 2,4-toluene diisocyanate: 2,6-toluene diisocyanate: 4,4'-isocyanate: bis- [isocyanatopheny] methane polymethylene poly (phenyl isocyanate): isopron diisocyanate Sites, and other aliphatic, includes a heterocyclic and aromatic polyisocyanates, and any mixtures of such polyisocyanates.

Specific examples of diisocyanates that can be used include 1,6-hexane diisocyanate (such as commercially available from Bayer under the trade name HMDI), isophorone diisocyanate (such as commercially available under the trade name IPDI from Huls), tetramethylxylene Diisocyanates (such as those commercially available under the tradename m-TMXDI from Cytec), 2-methyl-1,5-pentane diisocyanate, 2,2,4-trimethyl-1,6-hexane diisocyanate, 1,12- Dodecane diisocyanate and methylene bis (4-cyclohexyl isocyanate) (such as desmoder from Bayer Commercially available under the trade name W, and high-functional isocyanates such as burettes of 1,6-hexane diisocyanate (such as desmoder from Bayer) Commercially available under the trade name W), isocyanurate of 1,6-hexane diisocyanate (such as desmoder from Bayer) Commercially available as 3390), isocyanurate of isophorone diisocyanate (such as desmoder from Bayer) Commercially available as Z-4370), reaction products of tetramethylxylene diisocyanate and trimethylol propane (such as Cytan from Cytec) Commercially available as 3160), and reaction products of 1 mole of trimethylol propane and 3 moles of toluene diisocyanate (such as desmoder from Bayer) Commercially available as L). The amount of di- or polyisocyanate included should be 3-30 phr. Preferably the amount is 8-15 phr.

Other components of the curable component include isocyanate groups and hydrolyzable groups, that is, other groups capable of forming crosslinks such as halogen, hydroxy, alkoxy, or acyloxy groups: epoxy-containing groups: mercapto groups: mercapto-containing groups: vinyl groups : Vinyl-containing group: other isocyanate group: other isocyanate-containing group: ureido group: ureido-containing group; Imidazole groups: or various known organosilanes containing imidazole-containing groups. Such compounds are known in the art.

Preferred crosslinking groups of isocyanatosilanes are alkoxy groups. Examples of suitable commercially available isocyanato-alkoxy silanes herein are silquests from the osi specificultis group. Gamma-isocyanatopropyltrimethoxysilane, available as Y-5187, and Silquest from osi There is a gamma-isocyanato propyl triethoxy silane available as A-1310.

(C) solvent

Solvents useful as carrier excipients for the coating compositions of the present invention may be organic solvents or other materials known to dissolve acrylonitrile-butadiene copolymers. Examples of organic solvents useful in the present invention include ketones such as methyl ethyl ketone, methyl isobutyl ketone, and diisobutyl ketone: acetates such as butyl acetate: toluene, xylene and derivatives thereof: nitropropane: and ethylene dichloride.

Typically, the solvent of the present invention is used in 70-97% by weight of the total coating composition, preferably 80 so that the coating composition has a total nonvolatile solids content of about 3-30%, preferably about 6-15% Used at -90% by weight.

The coating composition of the present invention may contain any other components, such as metal oxides, antioxidants, particulate reinforcements such as carbon black and pigments such as TiO2. Specific examples of metal oxides include zinc oxide, magnesium oxide, zinc sulfate, and lead oxide, and specific examples of fine reinforcing materials useful in the present invention include carbon black, precipitated silica, and fumed silica. Any particulate reinforcement may be used in various amounts up to about 50% by weight of the carboxylated hydrogenated acrylonitrile-butadiene copolymer.

The coating composition may be prepared by simply mixing the components by spatula or the like manually or by mechanical mixing or shaking. Typically the coating composition is applied to the elastomeric material and / or other substrates by dipping, spraying, wiping, brushing, etc., and then the coating is for a time ranging from about 30 minutes to 2 hours, preferably from about 45 minutes to 1 hour. It is left to dry. Typically the coating composition is applied to form a dry layer on a substrate having a thickness up to about 0.1-5 mils, preferably about 0.5-1.5 mils.

The coating composition is allowed to cure in about 2-24 hours at room temperature. Curing can be accelerated by exposing the coating to elevated temperatures, but this is not required.

temperament

In particular, the coating composition of the present invention is suitable for coating an engine installation device composed of vulcanized elastomer parts bonded to metal parts. In particular, the composition is an effective coating agent for curing elastomers with limited oil and solvent resistance. Such elastomers include natural rubber, styrene-butadiene rubber, polybutadiene rubber, ethylene-propylene and ethylene-propylene-diene rubber, polyisobutylene-isoprene rubber, polychloroprene rubber, low acrylonitrile content (<35%) Nitrile-butadiene rubber and the like. The coating composition may also be used for rigid substrates such as metals, plastics, ceramics and composites. This is especially useful for bonded rubber mounts containing elastomeric and rigid components.

Preparation of Elastomer Substrates for Coating

The elastomeric surface or substrate to be coated may optionally be pretreated with a chlorinating agent such as sodium hypochlorite and hydrochloric acid. The use of various chlorine treatment agents to prepare elastomeric materials for application of coating compositions is well known in the art. One of the combustion treatments is commercially available from Rod Corporation under the tradename CHEMLOK 7701. The chlorinating agent can be applied to the surface of the elastomeric material by brushing, dipping, spraying, wiping, and the like, which is then left to dry. Chlorine treatment agents tend to be very brittle and typically dry out in seconds or minutes.

The coating composition of the present invention has the surprising ability to properly bond the flexible elastomeric portion with the rigid metal portion such that the boundary between the flexible elastomer and the rigid metal can be adequately protected by the coating composition. Thus, the present invention is distinguished from many conventional protective coating compositions that only have the ability to bind one type of substrate to be protected.

The following examples are provided to illustrate the present invention, and the present invention is not limited thereto.

Example 1

The following example was prepared using Zetpol 2220, X-HNBR produced by Xeon Chemical. A suitable substitute is Durban KA 8889.

Elastomer coating solution was prepared as follows.

  Ingredient Description PHR

 X-HNBR Carboxylated Hydrogenated Nitrile-Butadiene 100.0

The formulation was dissolved in methylisobutyl ketone (MTBK, CAS No. 108-10-1) to a solids content of 12.0 wt%.

To 40 g of solution, bis- [isocyanatopheny] methane (diisocyanate) in 53% xylene was added at levels of 0.1 g, 0.5 g and 1.0 g. At the 0.1 g diisocyanate level, the solution was cured at room temperature for up to 16 hours and at 0.5 g the solution cured 30 minutes.

To 40 g of solution, 3-isocyanatopropyltriethoxysilane, CAS # 24801-88-5, was added in amounts of 0.3, 0.7, 1.0 and 1.3 g. At all levels, the coating composition began to cure within 45 minutes to 1 hour and fully cured in less than 16 hours.

Fuel resistance test

Chemlock A coating test was performed on 55 durometer natural rubber compound (A135Q) treated with 7701. The coating was then compared with commercial fluorocarbon coating PLV-2100, commercial HNBR SPE XV and uncoated controls according to US Pat.

When immersed in the jet A fuel at room temperature for 24 hours, the obtained volume% swelling result is as follows.

Control (uncovered) 192.9%

Control PLV 2100 0.1%

Contrast HNBR SPE XV 33.6%

2.2% coating with bis- [isocyanatopheny] methane (Example)

Covered with 3-isocyanatopropyltriethoxy silane (Example) 2.3%

Adhesion test

Two 1 inch wide strips were joined together and pulled to 180 ° peel to test rubber adhesion. Rubber strip Prepared from 55 Durometer commercial natural rubber compound (A135Q) treated with 7701. A portion of about 2 inches in length was covered and each strip was placed in contact with each other and a weight of 472 g was applied to ensure intimate contact. Leave the weight in place for 10 minutes. After 8 days of drying, each strip is tinius olsen Removed from the tensile tester. The table below records the results.

 Cover type  Peeling Result (Lbf)

Contrast PLV 2100 2.03

Contrast HNBR SPE XV 8.52

Covered with bis- [isocyanatopeni] methane (Examples) 15.5

Coating with 3-isocyanatopropyltriethoxysilane (Example) 21.1

A metal bond shear test was conducted by bonding a 1 inch wide rubber strip to a 1 inch metal coupon with a 1 inch square overlap. Rubber strip Prepared from 55 hardness natural rubber compound (A135Q) treated with 7701. Metal coupone was 304 stainless steel. Stainless steel was chosen because it is known to be a difficult substrate to bond to. After coating, each of them was placed in contact with each other and a weight of 472 g was applied to ensure intimate contact, leaving the weight in place for 10 minutes. After drying for 8 days, each test piece was removed from a Tinius Olsen tensile tester.

  Cover type   Bonding Result (psi)

Control PLV 2100 16.78

Contrast HNBR SPE XV 19.23

Covered with bis- [isocyanatopeni] methane (Examples) 18.2

Coating with 3-isocyanatopropyltriethoxy silane (Example) 18.5

Ozone resistance

The ozone test was conducted using a dynamic ozone test (ASTM-D 3395) at 50 pphm ozone at 104 ° F.

The test pieces are based on 55 hardness-based commercial sulfur-cured natural rubber / polybutadiene mixtures protected with wax and alkyl-aryl phenylene-diamine anti-ozone agents (M122N) for anti-ozone. Under dynamic conditions, carboxylated hydrogenation coatings appear to be more effective than HNBR coated SPE XV as ozone barrier.

Crack Initiation

Control (uncovered) 6.5 hours

Contrast HNBR SPE XV 6.5 Hours

Uncracked at 28 hours with bis- [isocyanatopeni] methane (Example 1)

Coated with 3-isocyanatopropyltriethoxy silane (Example 1) uncracked at 28 hours

In addition to having a low adhesion value, the PLV 2100 coating cracks and peels off the rubber surface after bending. Microporous Dematia flexural specimens (prepared from 55 hardness-based natural rubber compounds) were coated with these same coatings and flexed according to ASTM D-813. The PLV 2100 coating severely cracked and peeled off when the substrate was exposed up to 4000 cycles. The baked HNBR SPE XV and Example 1 were run 80,000 cycles, at which time the natural rubber substrate cracked. There was no sign of delamination anywhere in the coating of the examples.

Claims (19)

A solvent-based coating composition containing 3-30% by weight of a solid, the solid comprising: (a) a carboxylated hydrogenated copolymer comprising repeating units from conjugated diene, unsaturated nitrile, and carboxyl monomers, (b) at least A coating composition comprising a cured component containing one isocyanate group and another group forming a crosslink, and (c) a solvent. The conjugated diene according to claim 1, wherein the conjugated diene is 1,3-butadiene: 2,3-dimethylbutadiene: 1,3-pentadiene: 1,3-hexadiene: 2,4-hexadiene: 1,3-heptadiene: A coating composition, characterized in that it is selected from a group consisting of piperylene: and isoprene. The coating composition of claim 2 wherein the conjugated diene is 1,3-butadiene. The coating composition according to claim 1, wherein the unsaturated nitrile corresponds to the following formula. Wherein A is hydrogen or a hydrocarbyl group having 1-10 carbon atoms. The coating composition of claim 1 wherein the unsaturated nitrile is acrylonitrile or methacrylonitrile. The coating composition of claim 1, wherein the carboxylated hydrogenated copolymer has an unsaturated level between about 0.1-20 mole percent. The coating composition of claim 6, wherein the unsaturation level is between about 3-7 mole percent. The coating composition of claim 1, wherein the solvent is selected from the group consisting of ketones: acetates: toluene, xylene and derivatives thereof: nitropropane: and ethylene dichloride. The coating composition of claim 1, wherein the curing component is di- or polyisocyanate. The di- or polyisocyanate of claim 9, wherein the di- or polyisocyanate is 1,6-hexamethylene diisocyanate: 1,8-octamethylene diisocyanate: 1,12-dodecamethylene diisocyanate: 2,2,4-trimethylhexamethylene di Isocyanate: 3,3'- diisocyanatodipropyl ether: 3-isocyanatomethyl-3,5,5'-trimethylcyclodecyl isocyanate: hexamethylene diisocyanate: 4,4'-methylene bis (cyclohexyl isocyanate) ): Cyclopentalene-1,3-diisocyanate: cyclodexylene-1,4-diisocyanate: methyl-2,6-diisocyanato caprate: bis- (2-isocyanatoethyl) -fuma Rate: 4-methyl-1,3-diisocyanatocyclohexane: trans-vinylene diisocyanate: 4,4'-methylene-bis (cyclohexyl isocyanate): methane diisocyanate: bis- (2-isocyane Itoethyl) Car Bonate: N, N ′, N ″ -tris- (6-isocyanato hexamethylene) Burette: toluene diisocyanate: xylene diisocyanate: dianisidine diisocyanate: 4,4′-diphenyl methane diisocyanate: 1-ethoxy-2,4-diisocyanato benzene: 1-chloro-2,4-diisocyanato benzine: bis (4-isocyanatophenyl) methane: tris (4, isocyanatophenyl Methane: naphthalene diisocyanate: 4,4'-biphenyl diisocyanate: m-phenylene diisocyanate: p-phenylene diisocyanate: 3,3'-dimethyl-4,4'-biphenyl diisocyanate: p- Isocyanatobenzoyl isocyanate: tetra chloro-1,3-phenylene diisocyanate: 2,4-toluene diisocyanate: 2,6-toluene diisocyanate: 4,4'-isocyanate: bis- [isocyanatopheny Methane polymethylene poly (phenyl isocyanane) ): Isophorone diisocyanate: and coating compositions, characterized in that the selection from the group consisting of a mixture thereof. 10. The coating composition of claim 9, wherein the di- or polyisocyanate is present at 3-30 parts by weight based on 100 parts by weight of the carboxylated hydrogenated copolymer of conjugated diene, unsaturated nitrile and carboxyl monomer. The coating composition according to claim 10, wherein the di- or poly isocyanate is present in an amount of 8-15 parts by weight based on 100 parts by weight of the carboxylated hydrogenated copolymer of conjugated diene, unsaturated nitrile and carboxyl monomer. The coating composition of claim 1, wherein the curing component is an organic silane containing an isocyanate group and other groups capable of forming crosslinks. 13. The coating composition of claim 12, wherein the hydrolyzable group is selected from groups consisting of halogen, hydroxy, alkoxy, and acyloxy groups. The group according to claim 13, wherein the group capable of forming a crosslink is an epoxy-containing group, a mercapto group, a mercapto-containing group, a vinyl group, a vinyl-containing group, another isocyanate group, an isocyanate-containing group, a ureido group, or a ureido-containing group. And a group consisting of an imidazole group and an imidazole containing group. The coating composition of claim 13, wherein the organosilane is isocyanato-alkoxy silane. 17. The coating composition of claim 16 wherein the isocyanato-alkoxy silane is gamma-isocyanato propyltrimethoxy silane or gamma-isocyanatopropyltriethoxy silane. Applying the solvent-based coating composition of claim 1 to the surface of a vulcanized rubber substrate bonded to a metal, drying the coating and then allowing the dried coating to cure in ambient conditions, in any case by application of heat Method of coating a substrate made with. In a bonded composite of metals bonded to a flexible elastomer, the composite is coated on the metal at least partially near the entire surface of the elastomer and around the elastomer, the coating comprising (a) conjugated diene, unsaturated nitrile, and From a carboxyl hydrogenated copolymer comprising repeating units from a carboxyl monomer, (b) a cured component containing at least one isocyanate group and other groups forming crosslinks, and (c) a solvent Binding complexes characterized in that formed.